


Spontaneous Lubrication

by castielsstarr



Category: Supernatural
Genre: Alpha Dean, Alpha/Beta/Omega Dynamics, Coming Untouched, Knotting, M/M, Omega Sam, Plot What Plot/Porn Without Plot, Rimming, Spells & Enchantments, slightest reference to breeding!kink
Language: English
Status: Completed
Published: 2016-01-04
Updated: 2016-01-04
Packaged: 2018-05-11 16:51:13
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,055
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5633998
Author URL: https://archiveofourown.org/users/castielsstarr/pseuds/castielsstarr
Summary: <blockquote class="userstuff">
              <p>While on a hunt, a witch hits Sam and Dean with a spell that causes them to take on the qualities of an alpha and omega. Needless to say, they don’t quite know what the heck is going on.</p>
            </blockquote>





	Spontaneous Lubrication

**Author's Note:**

> This was a lot of fun for me to write, and I hope you all enjoy it! Barely proofed once, so if you find any obvious errors, shoot me a comment and I'll make the fix. Thanks!
> 
> Come hang out with me on Tumblr, I promise I don't bite:  
> SPN NSFW Multi-ship sideblog: [wingedwincest.tumblr.com](http://www.wingedwincest.tumblr.com)  
> Main blog: [castielsstarr.tumblr.com](http://www.castielsstarr.tumblr.com)

“I can’t believe that witch freakin’ got away from us! You were supposed to be watching her,” Dean griped as he closed the door to their motel room and dropped his duffle by the door.

“Christ, just let it go, ok? I screwed up. At least she didn’t zap us with anything. So, that’s got to count a little.”

“All right, fine. I’ll let you have that one. We could have gotten a gender swap spell or something. Yeesh.” Dean shivered at the thought.

Sam flopped onto the bed closest to the door, feet hanging off the edge, not bothering to take his shoes off yet. He sighed as his back cracked and settled, providing a little endorphin relief from the stress of the failed hunt. The witch shouldn’t have been able to beat them, but stranger things had happened.

“I’m taking the first shower,” Dean said, striding toward the bathroom door, in the process of taking his shirt off over his head. “Don’t fall asleep yet. You know how much you hate going to bed dirty.” He chuckled a bit and threw his shirt at Sam, and it landed on his chest. 

The door clicked shut behind him and Sam heard the tiny noise of the lock. Not surprising—Dean didn’t like to be bothered in the shower. He had learned that the hard way when he went to surprise his brother with some morning shower kisses and he ended up being mistaken for an intruder and almost getting punched.

Dean’s shirt that lay resting across his chest smelled like a mixture of the outdoors, some dirt, a little blood and a lot of sweat. It was a heady kind of smell—strong enough to make him a little fuzzy around the edges. Sam picked it up with the intention of moving the thing off of him, fingers tight in the material, ready to throw it across the room. 

What happened, much to his surprise, was that he lifted it up to his nose and inhaled deeply. The fabric, which was nothing more than a regular black t-shirt from Walmart, felt so soft in his hands that he nuzzled his nose into it. God, it was almost like satin where it touched his cheeks, skin apparently hypersensitive. His dick started to harden in response.

Sam pulled the shirt away, and frowned lightly. Sure, he had been attracted to just his brother’s scent before, but usually it was only when he was fresh out of the shower or one of the rare occasions when Dean would wear a bit of cologne that he had found inside of a magazine and rubbed against his wrists. The fact that he was enjoying the scent of Dean when he was dirty and sweaty was unexpected.

He shifted to get up from the bed and put Dean’s shirt on top of his bag when he felt a slight wetness between his legs. That was… that was a little weird. He couldn’t really remember if they had done anything last night—he had just been so tired—but he knew they didn’t do anything this morning. That shouldn’t have been leftover lube, right?

When he moved around the small table toward Dean’s bag, Sam’s vaguely attentive dick brushed against the back of one of the chairs when he turned. The slippery feeling in his boxers actually increased and he knew that it couldn’t have been lube.

With the shirt tucked securely into Dean’s bag, Sam moved back to his bed and wiggled out of his jeans and boxers, leaving his long t-shirt on. They were just pulled down around his legs when he reached behind him and felt… what in the hell? 

He was completely wet with some sort of slick fluid and when he moved his finger just a little bit deeper between his ass cheeks to feel the pucker of muscle, another spurt of it released. Simultaneously, his throat released a groan of pleasure and he didn’t know why this was different. He stroked over his hole again and the next groan was accompanied with a full-body shiver. It just felt so fucking good, but why was there—for all intents and purposes—lubricant of some sort dripping from his ass? 

Sam started putting two and two together. Something definitely wasn’t right about this.

He had to fully remove the pants and underwear. A whine came out of him when he pulled his finger away from his hole and he bit down on his lip—not that it was going to do him any good. He needed to tell Dean what was going on. Something was up and if it happened to be a time-critical something, his brother needed to know now.

“Dean?” He knocked on the bathroom door repeatedly, never taking a pause. “Dean, I need to talk to you.”

“What is it?” Dean shouted through the door as the water continued to run.

“Can you please come out here? I think there’s something wro—” The door yanked open, Dean standing there wrapped in a towel at the hips, rivulets of water running down every part of his body.

“The fuck is—Sammy?” He started to admonish before seeing Sam’s completely spooked expression. He held the shirt down over the front of his groin, which was only a part of the problem, but he felt like he needed to cover it anyways.

“That witch, I think she did something to me.” He toyed with the hem of the shirt, holding it against his pale thighs. “I don’t know what, just something weird…”

Dean stepped closer to his brother, barely inches from touching him. Sam had tucked his chin and looked at the floor. His expression had changed so that he was only a tiny bit frightened, but mostly embarrassed. The air around them smelled a little sweet and he wondered if Sam had nabbed a different cologne the last time they were at the store. “Why do you think that?”

Sam stepped forward into his brother’s space, the water from Dean’s chest wicking into the fibers of his t-shirt where they touched. Dean couldn’t help inhaling the intense smell of Sam when he closed the space between them. His nose tilted toward the soft spot behind Sam’s ear and scented him. God, whatever it was, he smelled incredible. There was actually a small rumble building in his chest, but he wasn’t sure what that was about.

What he didn’t expect was for his little brother to grab at his wrist and slide his hand back behind him, down the crease of his ass to finger at his wet entrance. Sam whimpered and that rumble in Dean’s chest released as a growl. He grabbed tight to the swell of each of Sam’s pert cheeks. “So, you warmed yourself up for me. I like a brother who takes initiative.” He bit down on the pulse in Sam’s neck and Sam shivered, knees threatening to buckle.

“Dean, this is the problem. I didn’t do this for you. It did it itself.”

“You mean your ass just spontaneously lubricated?”

Sam nodded and dropped his head to Dean’s shoulder to hide the embarrassment. “And it just feels, better, stronger... I don’t know. It’s jus—oh god.” Dean teased that fingertip around Sam’s hole again and it was all he could do to keep his legs underneath him. He wanted to crumple, fall to his knees, but Dean held him close.

“Damn, Sammy. It really does feel good doesn’t it?” The only reply was a high keening before Sam attached his mouth to Dean’s neck and sucked a hard bruise there. “Can you even imagine what my dick would feel like in there?” The shiver ran through his entire body, causing his hips to rut forward against Dean’s towel-covered groin.

“I need it. Fuck, please.” The begging kept coming in one long strand all along Dean’s skin. He felt like he was honest-to-god going to die if he did not get his brother inside of him soon. He felt like he had a fever with the way his skin felt like fire, but he was still clammy. This wasn’t good at all.

Dean was having an equally hard time. He kept growling at Sam’s noises and that scent that clung to him. And his dick fucking _hurt_. Right near the base of it, it felt like the skin was stretching wider. “Shit, you’re right. She got us with something. I don’t know what the fuck this is.” He dropped the towel from around his waist and rutted against Sam’s hip.

They both groaned at the friction, Dean louder than Sam for once. It wasn’t quite relief, but it felt good having that contact of smooth skin. “Some kind o-of sex spell?”

“Oh, no shit.” He slid his index finger inside of Sam all the way to the second knuckle and the noise that came out of Sam was so goddamn obscene that it caused his jaw to drop. And Sam’s insides felt incredible. The way his rim fluttered around the intrusion and the slick that coated him so thickly that Dean could probably push in without any prep—it was all just too much. “Sam, I’m sorry. I know this is a spell, but—” he was interrupted when a growl forced it’s way from his throat. “But, shit, I can’t fight this, man.”

Sam forced his way from Dean’s grasp the next time the finger slid away from his ass. He pushed at his brother’s shoulders and got out of his grasp crossing to the bed in the least number of steps possible. The idea was to seductively make his way onto the bed and get Dean to join him, but he wasn’t capable of grace. His shins hit the edge of the bed and he scrambled up onto his knees. It felt so natural, the way his back arched, forcing his legs wide and ass in the air.

The rumble from behind him reached his ears maybe three seconds before there were hands on him. Dean didn’t have this many hands when he had looked at him before, Sam was sure of it. But the way his touch seemed to linger even after the hands had already moved on was heating him further. The lips pressed against his shoulders, back, and thighs, was even worse.

When Dean nipped lightly at the flesh of one thigh, Sam felt that tight ring of muscle clench and the slick that had been contained to just the cleft of his ass started to trickle down the inside of his thighs. It touched the edge of Dean’s lip and he couldn’t help when his tongue darted out to lap it up. 

That. That was where the sweet smell was coming from.

“Sam,” his voice wavered more than it should have. It was almost a whine and fuck if he would whine for anything. He cleared his throat and tried again, but it didn’t help. “Sam, I’m sorry.” He knew what he was about to do was something that Sam was always hesitant about, but he wouldn’t be able to hold back. He needed as much of that sweet taste as he could.

“What are you—FUCK.” There was not tentative licking, just a tongue pressing passed his rim and an open mouth sucking sharply. If Sam needed gentle he would have told Dean to stop or made a sound like he was hurt. What he was getting in return to each thrust into his baby brother was breathy cries and moans that the neighbors definitely would have heard if he hadn’t pulled a pillow down from the head of the bed and shoved his face in it.

When Sam tried to speak, his words were broken up by forced whimpers. “Oh my god, Dean… if you don’t stop… I’m going to come on your tongue.” Whatever force was controlling him allowed Dean to pull his face away from his brother’s ass and Sam’s moans softened to pants. “I need you to fuck me… now.”

Dean straightened and let two fingers circle around Sam’s slick rim, but Sam pulled his hips forward. “Not your fingers,” he panted. “Just, please.”

Jesus, he wanted Dean to just fuck straight into him.

He should have asked if that was really ok, should have asked if he was ready. None of that happened, though and Dean lined himself up before pushing in with one long stroke. Fuck, Sam shouldn’t have been able to accommodate him like that with no prep. It was tight as hell, yeah, but this still was unnatural.

When he tried to keep still, let Sam adjust to the sudden intrusion, his little brother moaned and started to fuck himself back against Dean. Sam’s insides felt like they were trying to milk his dick, clenching, tugging and fluttering around his length. This feeling was what he needed. He knew this was what the spell needed and he could feel his orgasm coming faster than it had even when he was a teenager.

That’s when he paid renewed attention to the stretching feeling around the base of his dick. Where it had just felt strange earlier, now it was starting to look strange, too. There was an actual bulge appearing in a ring. It wasn’t large yet, but he could feel the skin continuing to stretch the closer he got to finishing. He knew what that was. Fuck, they were in trouble.

“Shit, Sam, you need to stop. This isn’t good.”

“I’m not sure I can. Not sure, _mmm_ , not sure I want to.” He kept pressing back onto his brother’s cock, a warm pressure building in his abdomen. That feeling, at least, was familiar to him and he knew it was going to make him feel better.

“Brother, I’m not sure what this spell is for, but you know how like wolves and dogs mate?”

“Yeah, but why are we talking about this now?”

“Because I’m about to pop a knot if you don’t stop.”

There was a momentary still in Sam’s hips to process the information. “A knot? Like… really?”

“Yes, Sam. If you keep fucking me, I’m going to be forced to tie myself to you. For some reason this spell wants us to fuck like real animals. It’s not just an expression.” Sam tried to force back again, but Dean caught his hips and held him still, as hard as it was. He just wanted to fuck, to spill inside his brother and tie them together. These weren’t his thoughts, he knew this; it was just the spell.

Sam shook his head after a moment of thinking. “Do it. I don’t care. Fuck, knot me, please.”

Nothing could stop him from taking it then. He slammed his hips repeatedly into Sam, mercilessly taking what he needed. That keening noise was back as Sam wept openly, head turned away from the pillow. Those noises drove Dean faster and harder, and he would be concerned that Sam didn’t want this if it weren’t for the fact that he was pressing back into each thrust.

When that ridge started swell even more, Dean leaned down over Sam’s back, pressing them close together, his mouth working at the back of Sam’s sweaty neck. It should have been gross, but the spell was making every fluid coming from Sam’s body sweet and necessary.

“Dean, I’m… I’m really close, ohhh.” He was in the process of reaching around to wrap a hand around Sam’s cock when he felt him spasming around his dick, sucking the partially formed knot into him as his orgasm started rushing along his skin. It was so good that he started spouting off at the mouth. “Fuck, oh god, mine, fucking breed me, mate, _alpha_.”

Those last words and the meaning they held were the tipping point for Dean as his knot expanded to full size, locking him deep inside Sam. The orgasm was so intense when it hit him that he bit sharp into his brother’s neck. His groans and even whines were muddled against skin and the bit of blood filling his mouth.

Sam’s muscles worked around his brother’s knot, pulling the orgasm longer. When it finally subsided enough, Dean unlatched his teeth from his brother’s neck and he kept kissing the reddened skin, mumbling soft “sorry”s wherever they landed.

They were both panting heavy for a while, but after a couple minutes, Dean was able to suggest that they shift to lay on their sides. He had already tested how far he could pull back before his knot would cause Sam to hiss in pain, so he knew how much room he had to work with. It took a bit of effort, but they were able to comfortably rearrange themselves.

Sam’s rim fluttered when Dean draped an arm over his middle and what came with it was completely unexpected. “Oh god, Sam. Shit, shit, shit.” Sam could feel more come splash up against his insides and his brother held on tight to him, hips grinding through a second orgasm.

When he had settled again, Sam chuckled. “Did you know that animals with knots can have multiple orgasms, usually with very little time between them?”

“Did you know you're still an annoying little bitch?” He laughed and Sam purposefully tightened down on Dean’s cock. “No, no, I’m sorry, please. Let me rest, please.”

Dean could feel all of Sam relax and still. “Am I bleeding?”

“A little. I didn’t mean for that to happen. I just felt like I needed your neck in my teeth and I bit harder than I meant to.”

“It’s ok,” Sam said as he snuggled backwards, closer to Dean’s chest. “Can we sleep now?”

“Yeah, Sammy. Sleep sounds good.”

Before drifting off to sleep, Dean heard Sam’s small voice whisper, “They call it a mating bite.” Dean wanted to respond, but he was too close to sleep to be able to pull back from it now.

When they woke the next morning, the bite was gone from Sam’s neck and when they decided to have sex again just to test that the spell was lifted, Dean didn’t pop a knot. They were in the clear, at least. Neither of them made a mention when Sam called Dean “alpha” again, either.


End file.
